Dyslexia is an inherent inability of otherwise average or above average intelligent humans to read fluently and/or to write words and sentences in an orthographically correct form. The socio-economical implications of dyslexia are significant and often devastating for the individual, who, in many cases, dramatically underperforms in school and profession.
Dyslexia occurs predominantly in Western world languages, including English, Spanish, German, or French. It is estimated that up to 10% of the population of the Western world suffers from minor or major forms of dyslexia, see Snowling “Developmental Dyslexia: A Cognitive Developmental Perspective,” Aaron, Malatesha Eds., Reading and Writing Disorders in Different Orthographic Systems, Kluwer Academic Publishers, pages 1-23, 1989.
Dyslexia appears in various forms, such as deep or surface, and developmental or acquired dyslexia, and at different levels of severity and strength. There are multiple causes for dyslexia, which are not fully understood. For instance, dyslexia can appear as a result of brain damage after an accident or stroke. Most often, however, dyslexia develops in early childhood and adolescence, see Denckla “A Neurologist's Overview of Developmental Dyslexia,” Temporal Information Processing in the Nervous System”, Talal et al. Eds., Annals of the New York Academy of Sciences, Volume 682, pages 23-26, 1993.
The irregularities in cerebral information processing underlying dyslexia are not fully understood, and are a subject of intensive research. There are various models for the acquisition of human reading and writing skills. It is widely believed that orthographically correct writing is acquired over three phases, a visual phase, a phonetic phase and a final semantic phase, see Reitsma “Orthographic Memory and Learning to Read,” Aaron, Malatesha Eds, Reading and Writing Disorders in Different Orthographic Systems, Kluwer Academic Publishers, pages 51-74, 1989.
A commonly employed theory for reading is a dual route model, which distinguishes between a phonological and a lexical route, see Coltheart “Lexical Access in Simple Reading Tasks,” Underwood, Editor, Strategies of Information Processing, pages 151-216, Academic Press, New York, 1978. However, that model does not provide a precise mathematical or procedural description of the disability, nor does it provide a therapy.
More recently, connectionist approaches, based on neural networks, attempt to explain language acquisition and dyslexia, see Seidenberg, McClelland “A Distributed Developmental Model of Word Recognition and Naming,” Psychological Review, Volume 96, Number 4, pages 523-568, 1989, and Harm, Seidenberg “Phonology, Reading, Acquisition, and Dyslexia: Insights from Connectionist Models,” Psychological Review, Volume 106, Number 3, pages 491-528, 1999. There, neural networks were successfully trained to mimic word learning and spelling. However, there was no description based on the theory of information and coding. Further, no therapy for lessening the effects of dyslexia was described.
Correlations between the occurrence of dyslexia and temporal information processing in the human brain was described by Wolff in “Impaired Temporal Resolution in Developmental Dyslexia,” Temporal Information Processing in the Nervous System, Annals of the New York Academy of Sciences, Volume 682, pages 87-103, 1993. In particular, he suggested that dyslexia is a symptom of an inherent weakness in the brain for the processing of visual-temporal and visual-sequential, information—as opposed to visual-spatial perception, which is fully or often overdeveloped in dyslexic people. It was also observed by Overly et al. in “Dyslexia and Music: Measuring Musical Timing Skills,” Dyslexia, John Wiley & Sons Publisher, Volume 9, Number 1, pages 18-36, 2003, that dyslexic children often develop difficulties in accurate or rapid musical timing. It has been hypothesized that musical training may be a remedy for such timing difficulties.
Numerous therapies of dyslexia have been described and applied in the prior art. Those treatments have mostly been developed in experimental psychology and require extensive work and regular sessions. None of the prior art utilizes a precise mathematical model of the information underlying words and sentences, or can quantify the information recoded for spatial perception.
Prior art computer-based exercises link words to their semantics and to pictorial information to support orthographic memory of a patient. Such methods, however, are limited to concrete words with obvious semantics or pictorial correspondence, such as “house”. Those methods are of limited use for abstract words, such as “nonetheless”.
Another prior art method represents words as 3-dimensional objects or scenes sculpted by a patient using deformable modeling mass such as clay, see Davis, Braun “The Gift of Dyslexia: Why some of the Smartest People Can't Read and How They Can Learn,” The Berkeley Publishing Group, 1994.
There are also commercially available systems that provide methods to learn orthography using a computer. The systems present words using pictures and/or sound, however, none of those methods are based on information theory.
Therefore, there is a need for a method for language acquisition to provide therapy for dyslexia that overcomes the problems of the prior art.